Autochthonous starter cultures and indigenous grape variety for regional wine production

Aims To characterize Oenococcus oeni strains isolated from North-Apulian wines where malic acid degradation is usually achieved by spontaneous fermentations, and to determine the influence of bacterial inoculation time on the malolactic performances in ‘Nero di Troia’ wine using a complete autochthonous microbial regime. Methods and Results: O. oeni strains from wines produced with the autochthonous (Apulia Region, southern Italy) grape variety 'Uva di Troia' were isolated, selected and characterized. MLST and VNTR analysis were used to investigate intraspecific diversity. O. oeni strains were tested in co-inoculation and in sequential inoculation, with two autochthonous yeast strains previously isolated from ‘Nero di Troia’ wine. After a preliminary screening using co-inoculation regime, the O. oeni strains were grouped in reason of the different behavior in malic acid performances. Results suggested that the efficient degradation of malic acid in co-inoculation is a strain-dependent characteristic. Conclusions Autochthonous yeast/bacterium combinations were identified as starter culture, and used in a co-inoculation approach, for vinification of regional wines. Significance and Impact of Study The ‘microbial terroir’ of typical fermented food and beverage production represents a dynamic sector of applied research in food microbiology. In this work we propose the use of autochthonous bacteria and yeast for wine production from an indigenous grape variety.